Body mass index, or BMI, is the most common tool used to describe overweight and obesity in children. But BMI does not adequately describe regional distribution of fat, such as in the upper body, which is a better predictor of some obesity-related complications such as hypertension, diabetes and heart disease. In a study, "Neck Circumference as a Screening Measure for Identifying Children With High Body Mass Index," published in the August print issue of Pediatrics (published online July 5), researchers tested the usefulness of measuring neck circumference to identify children with high BMI.